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arXiv · 1211.3265

Onset of Fokker-Planck dynamics within a Closed Finite Spin System

Hendrik Niemeyer·Daniel Schmidke·Jochen Gemmer
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Abstract

Relaxation according to Fokker-Planck equations is a standard scenario in classical statistical mechanics. It is however not obvious how such an equilibration may emerge within a closed, finite quantum system. We present an analytical and numerical analysis of a system comprising sixteen spins in which spatial inhomogeneities of the magnetization relax approximately in accord with a standard Fokker-Planck equation for a Brownian particle in a parabolic potential.

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Hendrik Niemeyer, Daniel Schmidke, Jochen Gemmer. 2012-11-14. Onset of Fokker-Planck dynamics within a Closed Finite Spin System. https://doi.org/10.1209/0295-5075%2F101%2F10010

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